Progress in our understanding of skin biology and disease has been greatly advanced by the use of epidermal cell cultures. The Keratinocyte Core is designed to support and attract new investigators in skin biology by providing a reliable supply of highly purified preparations of human and mouse epidermal keratinocytes at a reduced cost. In addition, the Core will train researchers in the development and use of these various cell culture systems. In cases where more permanent cultures are required, immortalization and long-term culture techniques will be applied to human and mouse keratinocytes. The Core will serve as a resource for: 1) storing these cells and bulk tissue culture supplies; 2) transmitting expertise and techniques for studying keratinocytes; and 3) providing access to larger equipment suitable for keratinocyte biology (e.g., a UV irradiation lamp box, a humidified variable aerobic workstation for hypoxia studies, and a Nikon inverted microscope integrated for live cell imaging of linear scratch wounds). The Core will also provide training and supplies for a three-dimensional organotypic model for human epidermis that permits analysis of factors controlling the formation and organization of this stratified epithelium during development and in wound healing processes. Collectively, the Core will offer the necessary materials and expertise for NU SDRC investigators to better develop novel cell and molecular based strategies towards curing skin diseases and will help foster new collaborations among groups with the common goal of understanding the biology of epithelial cells.